In order to reference a column or field using the the SharePoint object model, you often need to know its internal name. For example, when creating a CAML query, you can specify the field on which to search by providing its internal name. As opposed to the display name, which can be changed in the UI, the internal name is immutable. While the default display name and the internal name are often identical or similar, they can also be very different. The difference isn’t always consistent. For example, spaces in the display name can be removed, such as IsCheckedoutToLocal, or replaced with the hexadecimal equivalent, such as HTML_x0020_File_x0020_Type. Furthermore, the display name can be the same for more than one fields, so the internal name is the only way to distinguish between them.

You can quickly determine the internal name of a field using the UI:

1. Open the List Settings page
2. Under the Columns section, select a column to view the Edit Column page
3. The URL of this page includes the internal name in the query string. For example, the URL for the Created By field includes the following query string List=%7BF641CEF1%2DCDE2%2D49E1%2D9800%2D861A408EF890%7D&Field=Author. The value for the Field parameter, Author, is the internal name for Created By. Continue reading List of Internal Names for SharePoint Fields →